import numpy as np
arr=np.array([1,2,3,4,5])
print(arr)
print(type(arr))
arr1=np.array([[1,2,3,4,5],[2,3,4,5,6]])
print(arr1)
print(type(arr1))
print(arr1.shape)
#2.索引和切片
arr3=np.array([1,2,3,4,5])
print(arr3[0:3])
#3.运算
print([1,2,3]+[4,5,6])
print(np.array([1,2,3])+np.array([4,5,6]))